1. Field of the Invention
The present invention relates to a cleaning liquid and a nozzle plate cleaning method, and more particularly, to a cleaning method of cleaning a nozzle plate of an ink jet head and a cleaning liquid suitable for this cleaning of a nozzle plate.
2. Description of the Related Art
As described in Japanese Patent Application Laid Open No. 2005-145054, on an ink jet head of an ink jet printer, a nozzle plate on which a plurality of nozzles are formed is provided. In such an ink jet printer, the printing is carried out by adhering ink drops injected from nozzles of the nozzle plate onto a recording medium. When the ink drops are injected from the nozzles, a part of the inks will be adhered to a surface of the nozzle plate, so that there is a need to clean the surface of the nozzle plate regularly in order to remove the adhered inks.
In the ink jet printer described in Japanese Patent Application Laid Open No. 2005-145054, a wiping member is set in contact with the surface of the nozzle plate and the adhered inks are wiped off by moving this wiping member along the surface of the nozzle plate.
The ink jet printer described in Japanese Patent Application Laid Open No. 2005-145054 is a device for consumer use, which mainly uses papers as the recording medium. For this reason, the inks to be used are formed by components such that the permeability with respect to papers is given a high importance and they can be wiped off easily when they are adhered to metals or resins constituting the nozzle plate. Consequently, as described in Japanese Patent Application Laid Open No. 2005-145054, the adhered inks can be wiped off by moving the wiping member in contact with the surface of the nozzle plate, along the surface of the nozzle plate.
However, in the nozzle plate cleaning method described in Japanese Patent Application Laid Open No. 2005-145054, the following points are not taken into consideration.
In the ink jet printer for industrial use, glasses or resins will be used as the recording medium, and the inks to be used have the good adhesive property with respect to glasses and resins. For example, the inks in which inorganic pigments or metal oxides are mixed into polymers will be used. For this reason, there has been a problem that it is difficult to remove such inks when they are adhered to the nozzle plate. In particular, when it is attempted to wipe off these inks adhered to the nozzle plate by using a wiping member, an ink-proof film made of fluorocarbon resin that is coating on the surface of the ink plate in order to suppress the adhering of the inks to the nozzle plate will be worn. This is presumably caused as the inorganic pigments or metal oxides contained in the inks will function similarly as abrasives.